Processing and Structure of Paperboard With a Needled Middle Layer

Abstract

The possibility to change the fibre network structure of paperboard by using the needle punching method was studied. Needling was performed on the middle layer made from unbleached softwood kraft pulp at a dry content of 20%. The needled structure was studied by several microscopy methods, which showed that the fibres were redistributed mainly in-plane. Denser regions of the fibre network structure were observed close to the needle penetration sites. The local density was estimated to be 25% higher than that of the surrounding unaffected structure.

A Review of Recent Trends and Challenges in Computational Modeling of Paper and Paperboard at Different Scales

“…Further, deeper investigations concerning the optimization of the shear strength profile should be undertaken [189] and potential improvements to increase the peak bending angle in folding should be developed, e.g. by using a needled middle layer [131]. Last but not least, more sophisticated comparisons with results of alternative testing setups such as the Scott Bond Test could yield deeper insigth into the processes [63].…”